Design Principles of Transformer Sensors for Measuring Direct, Alternating, and Impulse Currents

Abstract

Power electronics includes a number of key elements without which it is impossible to construct static electric energy converters. A current sensor is one of such elements. An ideal current sensor must have a number of features: it must provide galvanic isolation; it must have good linearity, and it must be able to operate in a wide range of temperatures. It must be able to measure direct, alternating, and impulse current with arbitrary shape, and have the maximally wide pass band. The most widely used technologies do not make it possible to construct a device that would satisfy all these requirements. In this connection, it is necessary to find alternative ways of solving this problem. The lack of domestically produced current sensors with galvanic isolation that are permitted for use in special-purpose devices and able to measure direct and alternating current with arbitrary shape is a state-scale problem. In addition, the task of ensuring the replacement of imported components for electric power control, conversion, and distribution devices has been set forth. The article proposes two versions of transformer current sensors, presents the functional diagrams, computer models, and simulation results confirming the correctness of the theoretical device operation principles.